Quantum GIS API Documentation  1.8
Public Member Functions | Protected Member Functions
QgsDerivativeFilter Class Reference

Adds the ability to calculate derivatives in x- and y-directions. More...

#include <qgsderivativefilter.h>

Inheritance diagram for QgsDerivativeFilter:
Inheritance graph
[legend]
Collaboration diagram for QgsDerivativeFilter:
Collaboration graph
[legend]

List of all members.

Public Member Functions

 QgsDerivativeFilter (const QString &inputFile, const QString &outputFile, const QString &outputFormat)
virtual ~QgsDerivativeFilter ()
virtual float processNineCellWindow (float *x11, float *x21, float *x31, float *x12, float *x22, float *x32, float *x13, float *x23, float *x33)=0
 Calculates output value from nine input values.

Protected Member Functions

float calcFirstDerX (float *x11, float *x21, float *x31, float *x12, float *x22, float *x32, float *x13, float *x23, float *x33)
 Calculates the first order derivative in x-direction according to Horn (1981)
float calcFirstDerY (float *x11, float *x21, float *x31, float *x12, float *x22, float *x32, float *x13, float *x23, float *x33)
 Calculates the first order derivative in y-direction according to Horn (1981)

Detailed Description

Adds the ability to calculate derivatives in x- and y-directions.

Needs to be subclassed (e.g. for slope and aspect)

Definition at line 24 of file qgsderivativefilter.h.


Constructor & Destructor Documentation

QgsDerivativeFilter::QgsDerivativeFilter ( const QString &  inputFile,
const QString &  outputFile,
const QString &  outputFormat 
)

Definition at line 20 of file qgsderivativefilter.cpp.

Definition at line 26 of file qgsderivativefilter.cpp.


Member Function Documentation

float QgsDerivativeFilter::calcFirstDerX ( float *  x11,
float *  x21,
float *  x31,
float *  x12,
float *  x22,
float *  x32,
float *  x13,
float *  x23,
float *  x33 
) [protected]
float QgsDerivativeFilter::calcFirstDerY ( float *  x11,
float *  x21,
float *  x31,
float *  x12,
float *  x22,
float *  x32,
float *  x13,
float *  x23,
float *  x33 
) [protected]
virtual float QgsDerivativeFilter::processNineCellWindow ( float *  x11,
float *  x21,
float *  x31,
float *  x12,
float *  x22,
float *  x32,
float *  x13,
float *  x23,
float *  x33 
) [pure virtual]

Calculates output value from nine input values.

The input values and the output value can be equal to the nodata value if not present or outside of the border. Must be implemented by subclasses

Implements QgsNineCellFilter.

Implemented in QgsAspectFilter, QgsHillshadeFilter, and QgsSlopeFilter.


The documentation for this class was generated from the following files:
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Friends Defines